John Lackey pitched 6 2/3 shutout innings and Josh Reddick had a two-run double as the host Boston Red Sox blanked the Baltimore Orioles 4-0 on Saturday night for their fifth straight victory.

Lackey (6-8) allowed three hits - all singles - struck out seven and lowered his ERA from 7.47 to 6.84.

Boston, which maintained its one-game lead over the New York Yankees in the American League East, scored three times in the fifth. Kevin Youkilis had an RBI double to left field to score Dustin Pedroia. After an intentional walk to David Ortiz, Reddick laced a double down the right field line.

Youkilis finished with three hits and two RBIs.

Derrek Lee was hit by a pitch from Lackey in the seventh and both benches were warned, one night after the teams were involved in a bench-clearing brawl.

Emergency starter Alfredo Simon (1-2) pitched well in defeat for Baltimore. Simon tired in the fifth and was charged with three runs on seven hits in his first start since 2009.

Baltimore has lost six straight.